The present invention relates generally to wheeled systems, and in particular, to wheeled systems having exemplary energy return features and methods of using and making same.
Since the days of ancient man, wheels have been used for a variety of purposes and with a variety of vehicles. Wheels have made possible carts, carriages, wagons, motorized and non-motorized vehicles, and the like, for the transportation of people and freight. The design of wheel assemblies for such items has focused on producing tires and wheels capable of accomplishing their intended use. Initially, this involved making wheel assemblies that were durable enough to travel over rough surfaces.
The invention of the automobile in the early 1900s, and the use of rubber and rubber compounds, increased the number and variety of wheeled systems. The introduction of air-inflated rubber tires resulted in a host of new design problems. A great amount of effort has been spent to make tires and wheel assemblies that have the desired resiliency and stability, maintain their integrity while inflated, are resistant to impacts and punctures, and the like. Great attention also has been given to developing various tread patterns to provide improved traction on paved or smooth surfaces.
One feature of tires and wheel assemblies which has not received particular emphasis involves the assemblies"" energy return characteristics. For example, while current automobile tires generally provide sufficient traction, their development has not focused on how the tires interact with the road surface to transfer energy in an idealized fashion. Hence, notwithstanding the extensive use of wheeled systems, room for drastic improvement still exists in the field of energy return.
The present invention provides exemplary vehicle wheel assemblies for use with a wide range of wheeled vehicles and apparatus. In one embodiment, the wheel assembly includes a first rim portion having a first circumferential edge and a second rim portion having a second circumferential edge. The first and second rim portions are coupled together to define a trough portion between the two edges. The wheel assembly includes a cartridge disposed in the trough portion between the first and second circumferential edges. The cartridge includes a chamber portion having a plurality of spaced protrusions, a resilient member disposed over the plurality of spaced protrusions, an actuator disposed over the resilient layer, and a traction layer disposed over the actuator. The actuator is adapted to compress the resilient layer at least partially into the chamber portion when the wheel assembly is loaded with a weight. In this manner, the wheel assembly is capable of providing energy return to the wheel assembly during rotation thereof.
In one aspect, the spaced protrusions are positioned to define at least two circumferential rings of protrusions. In another aspect, the chamber portion includes a generally trough-shaped chamber portion having first and second lips, with the resilient member in cooperation with and/or coupled to the first and second lips.
In a particular aspect, the resilient member has upper and lower surfaces, with the lower surface including a plurality of raised ridges. The raised ridges are positioned to be in cooperation with the plurality of spaced protrusions. The resilient member upper surface also may include a second plurality of raised ridges in cooperation with the actuator. The raised ridges increase the resilient member thickness at desired locations. In one aspect, the resilient member is about twice as thick at a location having one of the raised ridges compared to at a location devoid of the plurality of raised ridges.
In one aspect, the resilient member is in cooperation with and/or coupled to an outer rim of the chamber portion to define a generally hermetically-sealed chamber. In alternative aspects, the hermetically-sealed chamber has an internal pressure that is less than one (1) atmosphere (ATM), or is a vacuum chamber.
In one aspect of the present invention, the actuator comprises a cylindrical-shaped band, the band having a plurality of spaced apart holes formed therethrough. The spaced apart holes also may be positioned to define at least two circumferential rings of spaced apart holes. Preferably, the spaced apart holes are positioned to be in cooperation with the plurality of spaced apart protrusions in the chamber portion. For example, in one aspect the spaced apart protrusions in the chamber portion are adapted to extend at least part way into the spaced apart holes of the actuator when the wheel assembly is loaded with the weight.
In one aspect of the present invention, the traction layer comprises a cylindrical-shaped traction band, with the traction band having a plurality of spaced apart holes formed therethrough. Again, the spaced apart holes may be positioned to define at least two circumferential rings of spaced apart holes in the traction band, and also may be positioned to be in cooperation with the plurality of spaced apart protrusions in the chamber portion. Further, the spaced apart protrusions in the chamber portion may extend at least part way into the spaced apart holes of the traction band when the wheel assembly is loaded with the weight.
In one aspect, the resilient member is adapted to stretch at least part way into the spaced apart actuator band holes when the wheel assembly is loaded with the weight. The weight may include a motorized vehicle, a non-motorized vehicle, a person or persons, freight, and the like.
In alternative aspects, the traction layer comprises a substantially incompressible rubber, the resilient member comprises a rubber, and the chamber portion and the actuator comprise a nylon. The traction layer may, but need not, have a groove pattern defined on an outer surface thereof.
In another embodiment, a wheel assembly of the present invention includes a cartridge adapted to be coupled to a wheel rim between first and second outer rim edges. The cartridge includes a chamber portion having a plurality of spaced protrusions, a resilient member disposed over the plurality of spaced protrusions, an actuator disposed over the resilient layer, and a traction layer disposed over the actuator. The actuator is adapted to compress the resilient layer at least partially into the chamber portion when the wheel assembly is loaded with a weight. In one aspect, the cartridge is generally cylindrical and is disposed between the two rim edges.
In another embodiment of the present invention, a wheel assembly includes a traction layer disposed over an actuator, with the traction layer and actuator each having a plurality of holes disposed therethrough, and with the traction layer holes in alignment with the actuator holes. The assembly further includes a chamber portion adapted to be coupled to a wheel rim, the chamber portion having inner and outer edges defining a recessed bottom therebetween having a plurality of spaced protrusions. A resilient member is disposed between the chamber portion and the actuator. The resilient member is adapted to stretch into the chamber portion between the spaced protrusions, and is adapted to stretch at least part way into the actuator holes over the spaced protrusions.
In a particular aspect, the traction layer, actuator, chamber portion and resilient member are each generally cylindrical in shape, with the actuator and chamber portion having a greater hoop strength than the traction layer and the resilient member.